Jet action chemical feeding method

ABSTRACT

Apparatus for feeding a quantity of chemical into a stream of liquid by directing a jet of liquid onto a solid soluble body containing the chemical. A chamber receives a solid body of chemical composition which is soluble when exposed to a jet of water or other liquid. The feeding apparatus includes an elongated tube mountable at an inclined angle relative to a horizontal surface, and provided with a liquid inlet at a lowermost lower end to direct a jet of liquid in a longitudinal direction into the tube to impinge against a soluble body of chemical composition received within the tube. A liquid outlet opening is positioned at an uppermost elevation of the inclined tube, so that gas which is evolved from the chemical composition stick and which is not in solution in the liquid can nevertheless flow out of the feeding apparatus through the outlet opening.

This is a division of application Ser. No. 566,833, filed Apr. 10, 1975.

This invention relates in general to chemical feeding apparatus and inparticular to apparatus for adding a quantity of chemical to a liquidstream by gradual erosion of a soluble chemical composition.

Chemical feeding apparatus is known to the prior art which adds aparticular chemical substance to a liquid stream by directing the liquidstream onto a solid body of a soluble material which contains thedesired chemical to be added to the liquid. One example of suchapparatus is found in water conditioning apparatus used to add chemicalsto water being recirculated in liquid systems such as swimming pools, byway of example, in which chlorine must be added to the pool water. Thewater to be chlorinated is recirculated in a path including a solidchemical composition containing a chlorine substance. The chemicalcomposition slowly dissolves upon exposure to the flow of liquid,constantly releasing a controlled quantity of gaseous chlorine whichbecomes absorbed by the water being returned to the swimming pool. Otherexamples of solid-chemical feeding apparatus for adding a chemical to astream of liquid are known to those skilled in the art.

Prior-art chemical feeding apparatus of the foregoing type has generallyincluded some means for directing a liquid stream transversely to thelongitudinal axis of an elongate stick of soluble chemical composition,so that the chemical composition stick is eroded by the impact of thewater against the stick. Such prior-art apparatus, moreover, generallyrequires the stick of chemical composition to be maintainedsubstantially in a vertical position, with the transverse stream ofliquid striking the stick approximately near the bottom end of thevertical, so that the liquid-soluble stick is maintained by gravity in aposition which should ensure exposure to the incoming stream of liquid.

The use of stick feeding apparatus of the type known to the prior arthas certain disadvantages, among which is the requirement of asubstantial amount of vertical space required for insulation andplumbing of such apparatus. Stick chemical feeding apparatus isnot-infrequently installed in relatively cramped quarters, such as aswimming pool pump room or a similar location, and it is frequentlydifficult to find sufficient vertical clearance for installation of suchprior-art equipment. Moreover, it may be difficult to obtain the desiredrate of chemical dissolution because of the relatively small area of thechemical stick which is, at any given time, subject to impingement bythe incoming stream of liquid.

Accordingly, it is an object of the present invention to provide animproved apparatus for feeding a chemical into a liquid stream.

It is another object of the present invention to provide improvedapparatus for feeding a chemical into a liquid stream by flowing theliquid along a solid body of soluble chemical composition.

It is yet another object of the present invention to provide chemicalfeeding apparatus which can utilize an elongate stick of solublechemical composition and which has a relatively low physical profile.

Other objects and advantages of the present invention will be undestoodfrom the following description of a disclosed embodiment, including thedrawing in which:

FIG. 1 shows a pictorial view of a disclosed embodiment of the presentinvention;

FIG. 2 shows a section view taken along line 2--2 of FIG. 1;

FIG. 3 shows a section view taken along line 3--3 of FIG. 2;

FIG. 4 shows a section view taken along line 4--4 of FIG. 2;

FIG. 5 shows a section view taken along line 5--5 of FIG. 2;

FIG. 6 shows a broken pictorial view of an alternative disclosedembodiment of the present invention; and

FIG. 7 is an end elevation view of the embodiment shown in FIG. 6, withthe lower end cap depicted partially cut away for illustrative purposes.

Stated in general terms, the present invention includes a body defininga chamber for receiving a solid soluble chemical composition, with thebody being supportable on a horizontal surface so that the chamberoccupies an inclined position relative to the horizontal surface. Thelower end of the chamber is provided with a liquid inlet which can beconnected into a liquid flow system, and which directs a jet of liquidto the lower end of the chamber in a generally-longitudinal direction. Afluid outlet opening is provided at the upper end of the inclinedchamber, and the fluid outlet opening is positioned at the point ofmaximum elevation within the chamber. Gas which is evolved within theinclined chamber by erosion, decomposition, or other effects of theliquid jet impinging the soluble chemical composition within the chamberis completely removed from the chamber by the placement of the fluidoutlet opening, even if the gas has not become absorbed by the waterwithin the chamber.

Stated more specifically with respect to the disclosed embodiment of thepresent invention shown in FIGS. 1-5, there is shown a jet feedingapparatus indicated generally at 10 and having an elongate body member11 closed at the lower end by a lower end cap 12 and closed at the upperend by an upper end cap 13. The upper end cap 13 is provided with asupport stand 14 which depends downwardly from the upper end cap to bereceived on a horizontal support surface 15. The lower end cap 12 simplyrests on the horizontal surface 15 for support, causing the body 11 ofthe jet feeding apparatus to assume an inclined angular positionrelative to the horizontal surface. Although the exact angle of inclineis not considered to be critical in the operation of the present jetfeeding apparatus, an angle of inclination a of approximately 10° hasproved to be effective in an actual embodiment of apparatus constructedaccording to the present invention.

The body 11 in the disclosed embodiment may be generally tubular inconstruction, and may be made of any suitable material which isimpervious to water (or any other liquid flowing therethrough) and whichis not subject to attack by any chemicals contained in or released fromthe solid soluble chemical composition received within. In the case of ajet feeder apparatus used with appropriate soluble chemical compositionsintended to add chlorine to a water circulating system, for example, thebody 11 may be made of a material such as clear PVC tube. The body 11defines an elongate internal chamber 19 of tubular cross-section andhaving sufficient diameter to allow the generally cylindrical solidsticks 20a and 20b of soluble chemical composition to be looselyreceived within the chamber, with sufficient clearance between theexternal surface of the sticks and the interior wall defining thechamber 19 to provide an annular region 21 along which fluid can flow ina longitudinal direction alongside the exterior surfaces of the sticks.It is apparent from FIG. 2 that the longitudinal extent of the body 11is sufficient to accommodate two chemical sticks 20a and 20b arranged inserial manner within the chamber 19.

Each of the chemical sticks 20a and 20b is made of a suitable solidsoluble chemical composition which, when subjected to the flow of waterthrough the chamber 19 as described below, dissolves at a controlledrate to release a chemical substance. The released chemical substancegoes into solution with the water, or is carried by the water to flowout of the jet feeding apparatus. Specific details of the type andnature of the chemical compositions which may be incorporated in thechemical sticks 20a and 20b are available to those skilled in the art,and need not be recited herein.

Each of the chemical sticks 20a and 20b has an elongate interior passage22 extending therethrough, and the jet feeding apparatus can be providedwith an elongate rod 23 extending longitudinally within the length ofthe chamber 19 in alignment with the aligned interior passages of theserially-positioned sticks 20a and 20b. The rod 23, which has a diametersubstantially less than the diameter of the interior passages 22, isreceived at its lower end by a rod holder 24 which is retained withinthe lower end cap 12. The upper end of the rod 23 may be looselyreceived within the opening 25 of the removable end plug 26.

Referring to FIG. 5, it is seen that the rod holder 24 is spider-shapedto define a number of apertures 30 extending radially from the centralportion of the rod holder in which the rod 23 is received. The lower endcap 12 includes a liquid inlet connector 31 having an inlet opening 32which is somewhat off-center with respect to the center of the chamber19 and of the lower end cap. As best seen in FIG. 5, the off-centerposition of the inlet opening 32 allows liquid flowing through the inletopening to pass around the central portion of the rod holder 24, so thatsuch liquid is directed into the chamber 19 substantially as a jet ofliquid which is directed to flow in a generally longitudinal directionfor impingement against the lower end 33 of the chemical stick 20a.

The upper end cap 13 has a fluid outlet connector 34 defining an outletopening 35 in fluid flow communication with the chamber 19. The outletopening 35 communicates with the chamber 19 at the uppermost portion ofthe chamber upper end, as is particularly seen in FIG. 2. The upper endcap 13 defines an internal opening 36 which is sufficiently large toaccommodate the passage of the chemical sticks 20a and 20b, and which isselectively closed by the aforementioned end plug 26. The end plug 26may be removably connected to the upper end cap 13 by any suitableconnection such as the pipe threads 37, and an O-ring seal 38 may beprovided to ensure a fluid-tight seal of the closed upper end cap 13.

Considering the operation of the disclosed jet feeding apparatus, theapparatus is connected into a particular water circulation system sothat water flowing through the system is introduced to the jet feedingapparatus through the liquid inlet connector 31, with the consequencethat the water flows into the chamber 19 of the feeder in agenerally-longitudinal jet which impinges against the lower end 33 ofthe chemical stick 20a. The force of the water jet causes erosion of thelower end 33 of the stick, thereby releasing an amount of chemicalcomposition from the stick to be absorbed in or carried by the waterflowing through the jet feeding apparatus. The water also flows alongthe annular region 21 outside of the sticks 20a and 20b to cause furthererosion and dissolution of the sticks. Moreover, the sticks 20a and 20btend to be forced upwardly within the chamber 19 as a result of theimpact of the liquid jet against the lower end 33 of the stick 20a,allowing a portion of the inflowing jet of water to flow through thealigned elongate interior passages 22 of the chemical sticks. Erosionand/or dissolution of the chemical sticks thus occurs along threeregions of the sticks, namely, at the point of jet impact against thelower end 33 of the stick 20a, along the exterior surfaces of the twosticks, and along the interior surfaces which define the passages 22through the sticks. Where the chemical released by erosion and/ordissolution of the chemical sticks is released in the form of a gaswhich may not be immediately and entirely absorbed by the water withinthe jet feeder, the gas is allowed to be removed from the feeder byflowing through the uppermost-positioned outlet opening 35 withoutbecoming entrapped in an upper-elevation location of the feeder.

The state of erosion of the chemical sticks within the feeding apparatuscan be visually monitored by observation through the transparent body11, and the chemical sticks can be replaced simply by shutting off thewater circulation system and then removing the end cap 26 from the upperend cap 13. A pressure release valve 39 is provided on the upper end cap13 to permit the release of any hydrostatic pressure which may remainwithin the jet feeding apparatus, prior to removal of the end cap 26 forreplacement of chemical sticks.

A modified version of the embodiment described in FIGS. 1-5 is shown inFIGS. 6 and 7, where components which are common to the embodimentsdepicted in FIGS. 1-5 are identified by primed reference numerals. Asseen in FIG. 6, the jet feeding apparatus indicated generally at 10'includes a body 11' having a lower end cap 12', an upper end cap 13',and a support stand 14' depending downwardly from the upper end cap tomaintain the feeding apparatus 10' at an angle of elevation with respectto a horizontal support surface. The jet feeding apparatus 10' differsfrom the previously-described feeding apparatus 10, shown in FIGS. 1-5,by having a plural number of chemical sticks disposed in parallel flowrelation within the body 11', with each of the parallel-flow stickspositioned for impingement by a separate stream or jet of liquidentering the apparatus 10' through a separate corresponding liquid inletdisposed in the lower end cap 12'.

It is seen that the lower end cap 12' is provided with a plural numberof liquid inlet connectors 44a, 44b, 44c, 44d and 44e symetricallyarranged around the lower end cap. Each of the liquid inlet connectors44a-44e has an inlet opening 45 extending therethrough, in a manneranalogous to the inlet opening 32 extending through the connector 31 asshown in FIG. 2.

A plurality of chemical sticks 46a-46e, are disposed within the body ofthe jet feeding apparatus 10' in predetermined position to place aseparate one of the chemical sticks in alignment with the correspondinginlet opening 45 in each of the plural liquid inlet connectors. As seenin the cutaway portion of FIG. 7, for example, the chemical stick 46b isdisposed behind and in alignment with the inlet opening 45 in the liquidinlet connector 44b, while the chemical sticks 46c and 46e are similarlyaligned with the inlet openings 45 in the corresponding inlet connectors44c and 44e. The locations of chemical sticks 46a and 46d for theremaining two liquid inlet connectors 44a and 44d are shown inbroken-line in FIG. 7.

Separate elongate rods are mounted within the body 11' of the jetfeeding apparatus 10' to extend through the elongate passages 22' in thechemical sticks and to define the respective locations of each of thechemical sticks, with two such rods being shown at 47b and 47c in FIG.7. It will be understood by those skilled in the art that suitable rodholding apparatus can be provided within the body 11' to locate andsupport the rods 47b and 47c, as well as the rods corresponding to theremainder of the chemical sticks 46a-46e. It will also be apparent tothose of ordinary skill that the choice of five separate chemical sticksand corresponding liquid inlet connectors, as shown in FIGS. 6 and 7, isnot critical to the present invention; a greater or lesser number ofsticks can be provided. It will also be apparent, although notexplicitly depicted in FIGS. 6 and 7, that each of the chemical sticks46a-46e may actually comprise more than one single stick disposed inserial fashion along the corresponding elongate rod, in a mannercorresponding to the sticks 20a and 20b shown in FIG. 2.

The use of the embodiment shown in FIGS. 6 and 7 is substantially thesame as in the previous embodiment, with the exception that the severalliquid inlet connectors 44a-44e are connected in parallel through asuitable manifold or other liquid distribution arrangement to receiveliquid flowing through a particular water circulation system. The flowof water or other liquid into the jet feeding apparatus 10' ispreferably divided approximately evenly between the several liquid inletconnectors, so that each of the symmetrically-arranged chemical stickswill be eroded at approximately the same rate and will requirereplacement at approximately the same time, thereby minimizingmaintenance costs and down-time of the jet feeder. Water flows bothalong the inside and the outside of each of the chemical sticks, in themanner described previously, and exits through the fluid outletconnector 34' disposed at the upper most region of the upper end cap 13.As discussed previously, any evolved gas which is not entirely absorbedby the water within the jet feeder 10' will flow to the upper end of thefeeder for removal through the fluid outlet connector 34'.

It will be apparent that the foregoing relates only to a preferredembodiment of the present invention, and that numerous alterations andmodifications may be made therein within the scope of the invention asdefined in the following claims.

What is claimed is:
 1. The method of feeding a chemical into a liquid bydirecting a flow of liquid along a soluble chemical composition,comprising the steps of:directing a flow of liquid upwardly along aconfined path which is inclined with respect to horizontal; passing saidflow of liquid along at least one surface of a solid body of a solublechemical composition which may produce a gaseous fluid in response tosaid liquid flow; and removing said flow of liquid from an upper end ofsaid confined path, so that said gaseous fluid is removed from saidconfined path along with said liquid flow.
 2. The method as in claim 1,wherein said flow of liquid is directed to impinge against a surface ofsaid solid body, and is thereafter directed to flow in generallyparallel relation alongside a surface of said solid body while passingalong said confined path.
 3. The method as in claim 2, wherein said flowof liquid moves within said confined path alongside and in substantiallyparallel relation to a surface of said solid body.
 4. The method as inclaim 2, further comprising the step of:dividing said flow of liquidalong at least two flow portions within said confined path; and movingsaid flow portions of liquid in substantially parallel relation torespective surfaces of said solid body along said confined path.
 5. Themethod of feeding a chemical into a liquid by directing a flow of liquidalong a soluble chemical composition, comprising the steps of:directinga flow of liquid along a confined path; passing said flow of liquid insaid path along and in substantially parallel relation to at least onesurface of a solid body of soluble chemical composition which mayproduce a gaseous fluid in response to said liquid flow; and removingsaid flow of liquid and substantially all of said gaseous fluid fromsaid confined path of flow.
 6. The method as in claim 5, furthercomprising:impinging said flow of liquid against a surface of said solidbody, and thereafter flowing said liquid in said parallel relationalongside said solid body.